我有一个数据帧，看起来像这样
df <- data.frame("V1" = c(0,0,0,0,0,2,2,2,2,2),
"V2" = c(9,9,9,0,0,2,2,2,0,0))
I would like to create a stacked barplot in this fashion:
因此，基本上我将某个值映射到相应的 colored颜色 (9-白色(invisible)，0-绿色2-红色)，然后创建一个长度等于该值在DataFrame列中出现的次数的条形图.有没有办法做到这一点，比如使用ggplot2？
您可以使用pivot_longer将数据帧更改为长格式.例如，使用case_when添加一列，其中包含要显示的条形图的 colored颜色 .您可以使用scale_fill_identity将条形图填充为相应的 colored颜色 .要获得与数据帧相同的顺序填充堆叠条形图，您可以使用ggplot_build修改绘图数据，方法是用与数据帧相同顺序的矢量替换"Fill"列.您可以使用以下代码:
library(ggplot2)
library(tidyr)
library(dplyr)
library(scales)
# Create plot
p <- df %>%
mutate(index = 1) %>%
pivot_longer(cols = -index) %>%
mutate(color = case_when(value == 9 ~ 'white',
value == 0 ~ 'darkgreen',
TRUE ~ 'red')) %>%
ggplot(aes(x = index, y = name, fill = color)) +
geom_col(width = 0.3) +
scale_fill_identity() +
theme_classic() +
scale_x_continuous(expand = c(0,0), breaks = pretty_breaks(2)) +
labs(x = '', y = '')
# Extract vector of colors in right order
vec_colors <- df %>%
mutate(index = 1) %>%
pivot_longer(cols = -index) %>%
mutate(color = case_when(value == 9 ~ 'white',
value == 0 ~ 'darkgreen',
TRUE ~ 'red')) %>%
arrange(name) %>%
pull(color)
# right order colors
vec_colors
#> [1] "darkgreen" "darkgreen" "darkgreen" "darkgreen" "darkgreen" "red"
#> [7] "red" "red" "red" "red" "white" "white"
#> [13] "white" "darkgreen" "darkgreen" "red" "red" "red"
#> [19] "darkgreen" "darkgreen"
# use ggplot_build to modify data and replace fill column with vector
q <- ggplot_build(p)
q$data[[1]] <- q$data[[1]] %>%
group_by(y) %>%
arrange(x, .by_group = TRUE)
q$data[[1]]$fill <- vec_colors
q <- ggplot_gtable(q)
# plot
plot(q)
创建于2022-09-17年第reprex v2.0.2页